Clamp



Aug. 20, 1929. G. KRELL ET AL CLAMP Filed May 5, 1927 5 Sheets-Sheet l INVENTOR q Geo/5e /'f/'e// BY 62/ MMarf/hef ATTORNEY 6 1NVENT% 60/ e we S l Cm n 3 621 Mar/Mel.

'Aug. 20, 1929.

G. KRELL ET AL 1,725,459

CLAMP Filed May 1927 5 Sheets-Sheet 2 ATTORNEY 1929- GIKRELL ET AL I 1,725,459

- CLAMP Filed May 1927 5 Sheets-Sheet 3 A TTORNEY Patented Aug 20, 1929.

i UNITED STATES PATENT OFFICE.

GFDBGI AND GUY m'rmn'r, OI SAPULPA, omon; SAID manna-r ASSIGNOB -'1O SAID CLAIR.

Application filed Kay 5,

Our invention relates to clamps of a type employed for letting in and removing tubing and casing-to and from an oil well and commonly desi ated elevators or spiders, .5 the principal o j ect of the invention being to facilitate application of the clamp to the tubing or casing, automatic application of the gripping jaws or slips to the tubing or casing and control of the jaws or slips for facilitating release of the tubing or casing and return of the jaws or slips to normal relation with their carrier.

In accomplishing these objects we have provided improved details of structure, the preferred forms of which are illustrated in the accompanying drawings wherein:

Fig. 1 is'a perspective view of a clamp embodying our improvements, illustrated .in functional relation to a joint of tubing and hereinafter termed -a tubing elevator without intent to limit the invention-to such particularuse. I

Fig. 2 is a plan view of the elevator, parts being broken away for better illustration.

Fig. 3 is an enlarged detail perspective view of the elevator in open position.

Fig. t is an irregular vertical section on the line 44, Fig; 2.

Fig. 5 is a' vertical section on the line 5-5, Fig. 2;

Fig. 6 is a detail perspective view of one of the frame members.

Fig. 7 is a detail perspective view of one of the slip carriers.

85 Fig.8 is a detail view of one of the slips.

. Fig. 9 is an enlarged vertical section of the hinge joint between the frame members.

Referring more in detail to the drawings:

1 and 2 designate the paired frame members each comprising front and rear walls 34 and a floor 5, the floor being provided with an arcuate recess 6 to permit application of the frame members .to. the tubing. The rear walls 4 are provided with hin e barrels 7 receiving a pin 8-upon which t e respective halves of the frame may swin to open and close the frame. The. barrels are bac'kset from the rear walls 4 onarms f v 9 so that the free edges of the wall members of respective frame members may abut in *a ".vertical plane.

' The front wall 3 of the frame member 2 is provided with forwardly directed ears 10 carrying a hinge pin 11 and hingedly mounted on said pin is a latch 12 comprising the 1921. Serial no. mam.

arms 13 and head 14 adapted toswin over and receive a vertical rib 15 at the e go of the front wall of the opposite frame member 1. The latch 12 is yieldingly urged to its functional position by a spr1ng16, having end coils surrounding the hinge pin 11 I and anchored to the frame ears 10, and a central portion 17 extended forwardly and bearing against the front face of the latch head 14. The latch 12 carries a handle member 18 and the frame member 1 a handle 19 for facilitating opening and closing move- The slip carriers 24--25 comprise semi flask-like members, each comprising a downwardly tapered concave seat 26 co-operative with a similar seat on the mating carrier to form a downwardly tapering bore for a set of jaws or slips, the seat 26 terminating in an inset shoulder 27 formin" a stop for the slips and the lower edge 0 the carrier being tapered upwardly ,to the edge of the shoulder to facilitate downward application of the clamp over ajoint of tubing.

' Each of the carriers 2425 is intended for carrying a plurality of slips, preferably two, as illustrated in the present drawings, and to key the slips in the carrier for longitudinal opening and closing movement. and for lateral pivotal movement for adjustment on a tube, we provide the carriers with vertical grooves 28, each extending from near the top of the carrier to slightly beyond and through the shoulder 27, forming sockets 29 for seating the springs 30 which serve to restrain the slips in open position and to return the slips to open position after release of the slips from a tube.

Extending through the upper and lower edge portions of the carrier mto the upper,

and lower portions of the grooves 28 are bores 31 through which the anchoring pins 32 are passed, the pins having heads 33 at their lower ends seated within countersunk recesses 34 in the lower edges of the carrier and having nuts 35 at their upper ends seated on beveled bosses 36 on the upper edges of the carriers to accommodate the pin to the tapered angle of the slip seat and anchor groove. I p 6 Each'of the slips com rises a substantially quarter-round block 37 avinga concave mner face 38 provided with upwardly directed teeth 39 and having a taperedouter face and side edges to permit the assembled sllps to seat within the tapered bore of the carrier. On the outer face of each of the sllps 37 is an car 40 adapted for sliding fit in a vertical groove 28 in a slip carrier and having a vertical aperture 41 of sufiiciently greater diameter than that of the anchor pin 32 to permit the ear to slide readlliy over the pin when the parts are assemble On the up er end of each of the slips IS a finger 42 v aving a concave inner face 43 adapted for free movement over the outer wall of a tube and a flat upper face 44 adapted forengagement with the lower edge of a collar 45 of a tube 46 to interrupt travel of the slip and effect closing of the clamp about the tube as will presently be described.

The clamp is adapted for two opening and closing movements-one a hinged movement of the halves of the frame on the vertical hinge previously described, and the other a swinging movement of the slip carriers on transverse axes to permit the slips to swing toward and from the tubing to effect a grip ing relation of the slips on the tubing or re ease therefrom. The swinging of the slips and their carriers is on the trunnions 47 projecting from the front and rear inner corners of the carriers and seating in the sockets 20 in the front and rear walls of the frame members 1 and 2, the trunnions being located below and inwardly of thecenters of gravity of the carriers, so-that when unrestrained, thevcarriers. will swing' rearwardly to space the upper portions thereof away from the tubing to w clamp is applied, the extent of swinging movement of the carriers being limited by contact of their outer edges with the end walls of the frame members.

The clamp is suspended from bail members 49 hung in the derrick in any usual manner and seated in transverse sockets 50 in arms 51 extending from the upper portions of the slip carriers, the balls having .free pivotal movement in. the sockets to'ax-- lally support the carriers and held in place by keeper blocks 52 bolted to the arms 51 and covering the outer ends of the sockets to prevent escape of the bails, without limiting their axial movement.

Assuming that a clamp constructed and assembled as described is to be used for as follows:

until the fin ers 42 reach an ich the w the collar 0 der, the clamp is applied to the tubing by unlatching the frame members, swinging them outwardly on their vertical hln' e, bringin the clamp members about the (Al bing an then closing the clamp members to locate the tubing within the slips.

When the clamp is located about the tubing it may rest on the spider and weight of the slip carriers and of the sus ending bails will tend to spread the carrlers on thelr swinging mountin and thereby provide an adequate opening or receiving the tubing so that the clamp may be applied thereto. After the clam has been applied to the tubing and latch the bails are lifted, initial lifting movement tending-to close the carriers over. the tubing and continued lifting movement carrying the slips alon the tubing engage the coupling col ar on the up er end of the tubing (Fig. 1). When t is engagement takes place, the slips are held and their carriers moved upwardly along their tapered faces, compressing the springs 30. and forcing the slips inwardly to grippin relation with the tubing. When thls gripping relation is effected, the slips resume their lifting movement with the clam and carry the tubing with them because 0 the engagement of the upper ed es of the slip fingers with the lower edge of the coupling collar, and also because of a gripping relation of the slip teeth with the body of the tubing below the coupling collar; it being apparent that because 0 the secondary grip of the slips on the tubing, tendency of the collar to strip from the tubing under wei ht of the string of tubing supported there rom is obviated;

insure? retention of the tubing in case the if slip teeth should fail to hold the weight of the tubing. p When the joint of tubing has been elevated through the spider to a point where a succeeding joint is exposed, the upper omt is unscrewed and carried to one side of the platform. When the joint of tubing is let down ontb the platform and the clamp relieved from its wei ht, weight of the slip carriers, supplemente by weight of the bails, tends to spread the carriers away from the tubing, drawing the slips with them to remove the slips from gripping contact with the tubing. When the slips have been removed from their gripping contact with the tubing, the -springs 30 shift the slips outwardly in their carrier's, tending to open the sh s ready for application to another joint of tubing.

It is apparent from the foregoing that we have provided a clamp of this character which-may be easily and quickly applied to tubing or casing, which 1s semi-automatic in its operation in that it will open under its own weight and under tension of the slip spreading springs to prevent freezing of the slips in their carriers. v

It is further apparent that because of the tapered mountin of the slips in their carrier, there will be a reaction of the slips under load, but. that such reaction is ofiset by the leverage exerted on the carrier from the bail mounting on the carrier arm operating on the fulcrum provided by the trunnions whereby the carrier is pivotally mounted on its frame.

What we claim and desire to secure by Letters Patent is:

1. A clamp of the character described comprising frame members, carriers swingingly mounted in the frame members on horizontal axes, located below and inward of their centers of avity and having tapered seats, slips keyed to the carriers for longitudinal movement in said seats, and means supporting the clamp from the carriers.

2. A clamp of the character described comprising hlngedly connected frame members having side and end walls,..carriers pivotally mounted between the side walls and adapted for stop engagement with the end walls of respective frame members, tapered slips keyed to thecarriers, means yicldingly restraining the slips, and means connected with the carriers for suspending the clamp.

33. In a clamp of the character described, hingedly connected frame members comprising spaced walls having paired trunnion bearin s, carriers having trunnions seated in sai bearings and having tapered seats, tapered slips keyed to the carriers for longitudinal movement in said seats, and means suspending the clamp from the carriers.

chored on said pins,

4. In a clamp of the character described, frame members, carriers pivotally mounted in the frame members, comprising tapered seats having stop shoulders at their lower ends, tapered slips keyed to the carriers for vertical movement in said seats and limiting engagement with said shoulders, and

.means connected with the carriers for suspending the clamp,

5. In a clamp of the characterdescribed, frame members, carriers pivotally mounted in the frame members, comprising tapered seats having vertical grooves'in their side walls, pins extending through said grooves, tapered slips in said 'seats having ears projected into said grooves and pivotally anand means connected with said carriers for sus nding the clamp.

6. In a clamp of the c aracter described, frame members, carriers pivotally mounted in the frame members, comprising tapered seats having vertical grooves in their side walls, pins extending through said grooves,

tapered slips in said seats having ears proected into said grooves and pivotally anchored on said pins, springs in said grooves engaging said ears to restrain the sli s, and means connected with said carriers or suspending the clamp.

7 In a clamp of the character described, a frame, carriers swingingly mounted in said through the grooves,' downwardly tapered seats having shoulders at their lower ends and havin vertical grooves, pins extending through the grooves, downwardl tapered slips in said se'ats having ears extended into the grooves and pivoted on said pins to key the slips for vertical and pivotal movement in the carriers, springs seated in said grooves surrounding the pins and engaging said ears to restrain the slips, fingers on the upper ends of the slips for engaging a tubing collar, and means connected with said carriers for suspending the clamp.

8. In a clamp of the character described, hingedly connected frame members each comprising side walls and a back wall, a carrier swingingly mounted between the side walls of each frame member, on an axis forward of and below its center of gravity, and adapted for' engaging the back wall to limit its opening movement, tapered slips keyed to the carriers and means connected with the carriers above and rearward of their centers 01 gravity for suspending the clamp.

9. In a clamp of the character described, hingedly connected frame members each comprising side walls and aback wall, a carrier having trunnions mounting on the side walls, slips having tapered "seat in the carrier and hanger members pivotally supporting the carrier from points above and outwardly of the vertical planes of the trunnions to effect leverage of the slips against the object clamped thereby, to offset reaction imparted to the slips through their tapered mounting.

10. Aclamp of the character described including carrier supporting means, paired carriers pivotally mounted on said means below and forwardly of their centers of gravity to swing apart when unrestrained, means suspending the carriers outwardly of their mountings to close the carriers under weight of the carriers, and slips in said carriers for gripping an object when the carriers are closed.

11. A clamp of the character described including carrier supporting means paired carriers pivotally mounted on said means below and forwardly of their centers of gravity to swing apart when unrestrained, means suspending t e carriers outwardly of their mountingsto close the carriers under weight of the carriers, yielding slip supporting means in the carriers, and tapered slips slidable in said carriers against the tension of said yielding means to grip an ebjecteiui automatically returnable by said means when the carriers are opened.

' 12. A clump of the character described ineluding carrier supporting means, paired means suspending the carriers eccentrically.

of their mountings anci their centers of gravity to close the carriers under weight of the carriers and slips in said carriers for gripping an object when the carriers are closed.

In testimony whereof we aflix our signatures.

GEORGE KRELL. GUY M. MABTINET. 

